1. Field of the Invention
The field of art to which the invention pertains includes the field of flexible pipe fittings for lawn sprinkler systems, particularly, with respect to a pipe fitting having a rigid shape-retaining portion formed in the coupling section of the pipe.
2. Description of the Prior Art
In U.S. Pat. No. 3,759,455, there is illustrated a flexible pipe fitting which is used to interconnect a sprinkler and a pipe line and is usable to prevent damage and injury in the event the sprinkler or sprinkler riser is accidentally struck. The fitting is formed of a flexible tube with end members secured to opposite ends of the tube which form coupling sections for interconnecting the fitting to sprinkler heads or additional pipes. One difficulty with the aforementioned device is that the interconnection between the tube and the end members is such that a reduced interior bore is formed and pop-up type sprinkler heads do not have sufficient clearance to move in the junction area. Additionally, it has been found that the interconnection of the end members of the flexible tube tends to fail after a period of useage. One technique for improving the aforementioned fitting has been to integrally mold the end members and the flexible tube from a single type of material. However, by making the end members which form a thread coupling section of the same flexible material as the flexible tube, typically, i.e. PVC (polyvinyl chloride), it has been found that the sprinkler head threaded portion tends to deform the threaded coupling section. Additionally, it has been found that even after threading the coupling section to a device, if sufficient force is exerted on this junction, the threaded end of the coupling section can deform and be physically removed from the device.
In order to overcome the attendant disadvantages of prior art flexible fittings, the present invention provides an integrally formed body and coupling section and a rigid shape-retaining portion in the coupling section. The shape-retaining portion enables the coupling section to remain relatively constant when a member is secured to the threaded portion of the coupling section or when a force is exerted on the coupling section or the member secured thereto. Thus, separation of the coupling section and the adjacent structure to which it is secured, such as an additional pipe or a sprinkler head, is prevented.